Circuit breaker



J. P. ARNDT.

CIRCUIT BREAKER. APPLICATION FILED 00124, 1919.

1,403,373. Patented Jan. 10, 1922.

3 SHEETS-SHEET 1- may? j/izv/ P9777 .l. P. ARNDT.

CIRCUIT BREAKER.

APPLICATION HLED 001.24, 1919.

Patented Jan. 10, 1922.

3 SHEETS-SHEET 2.

ril

J. P. ARNDT.

CIRCUIT BREAKER.

APPLICATION F !LED OCT-24. 1919.

1,403,373. Patented Jan. 10, 1922.

3 SHEETS-SHEET 3.

. citizen oi the United States.

P. ARNDT, OF MILW'AUKEE, WISCONSIN.

CIRCUIT BREAKER.

T 0 all whom it may cow-0cm Be it known that l. Jonzv l".

r at Milwaukee, in the county of Ni} and State of lVISCiHlSHl. have invented new and useful Improvements in Circuit Breakers of which the following is a specification.

This invention relates to uit breakers.

One of the objects or": the inventi n is to provide an improved circuit breaker for use with contact slips. 7

Another object is to provide animproved circuit breaker which may be easily and quickly assembled. 7

Another object is to provide an improved circuit breaker the contacts or which when damaged by arcing may be readily replaced.

Another object is to provide an improved circuit breaker wherein the duration of the arcing between the contacts thereoi is reduced to a minimum.

Another object is to provide an im n'oved circuit breaker which may be eithe' auto matically or manually tripped.

Another 'object .is to provide an enclosed circuit breaker which is readily removable from its enclosing casing.

Other objects and advantages will appear from the specification and claims.

One embodiment of the invention is shown in the accompanying drawings in which-- Figure 1 is a side elevation of a circuit breaker, with the tubular support in section showing the circuit breaker in open condition. r

Figure 2 is a side elevation of the circuit breakerotFigure 1 showing the circuit breaker in closed condition Figure 3 is avertica-l section through the circuit breaker shown in Figure 1.

Figure 4' is a sectional View on line et-t of Figure 3. I s

Figure 5 is a sectional View on line 5'5 oi Figure 3. V

Fi ure 6 is a sectional view on line 6*6 of Figure 8.

Figure 7 is a sectional view on line 7-7 of Figure 3. i

Figure 8 is a perspective of the upper terminal and associated stationary main and auxiliary contacts of the circuit breaker.

Figure 9 is a perspective of the lower terminal of the circuit breaker.

Figure 10 is a side elevation of the tubular support with the lower terminal removed Specification of Letters Patent.

Patented Jan. 10,1922.

Application filed October 24, 1919. Serial No. 333,082.

to show the means for locking the upper and lower sections of the tubular support together.

Figure 11 is a perspective of the latch and dashpot mounted upon a supporting frame. and the armature and lever for releasing the latch. V

In general, the illustrated circuit breaker comprises a tubular support carrying two circuit terminals for cooperation with contact clips to hold the support in place and complete the circuit and a circuit interrupter within the support.

The circuit interrupter within the tu bular support has a pair of main contarts through which the circuit is primarily closed, and a pair oi. auxiliary or arcing contacts between which the circuit is finally opened. The main and auxiliary contacts are normally maintained in closed relation but are adapted to be opened upon the occurrence of predetermined abnormal conditions. When the contacts are opened. a blastof air is provided between the auxiliary contacts to aid in preventing or interrupting any arc which may tend to form or persist therebetween.v

Referring to Figures 1, 2 and 3 ot the drawingsthe upper section 1 of the tubular support of suitable insulating material, such as bakelite carries two circuit terminals 3 and 4 of copper positioned near opposite ends of the section The terminal 3 extends through aligned slots in the section 1 and a ferrule 5 provided thereon. The inner end of the ferrule 5 is crimped into a groove in the sectionl for so curing the ferrule thereto and for forming a tight fit therebetween. The inner end of the terminal 3 is formed into a cylindrical tube Twhich serves as the stationary main contact. A cap 6 removably clamped to the terrule 5 is provided with a lug which fits in the upper end ofthe contact tube 7 and cooperates with the slotted section 1 to hold the terminal 3 and the tubular contact 7 in position.

The stationary auxiliary contact of the circuit breaker is an annular disk 8 of copper having a projection 9 struck up therefrom to engage a slot in the main contact tube 7 for holding the annular disk against the lower edge 01"? the main contact tube 7. The opposite margin of the annular disk is brazed or soldered to a shoulder 10 on the blade terminal 3, A barrier ring 11 of in- V sulating material is held in spacedrelation to the annular diskvr8 bymeans of screws The inner end or" the lower terminal 4 1s provided. with two laterally extending arcu ate ears 13 and 14 by which the terminal is mounted on adferrule 15 on the lower end of the section-1 of the tubular support,

The

ipcr end of the ferrule15 is crimped into 'a groove in the support 1 for securing the ferrule thereto and for formingfa tight fit therebetween. A gulde finger 19 is provided for positioning the terminals in the contact '1 clips between which 1t 18 connected.

Two downwardly extending lugs 16 and 7 formed on the lower edge of the blade terminal 1 fornra bracket for supporting solenoid coil 18 the lower end of which is seated in and connected withthe bracket. 7 A. copper tube 20 mounted in the top of a brass piston 21 forms the movable main contact of the circuit breaker. A brass collar surrounding the tube 20 and insulated therefrom by an insulating sleeve 23 to whichit is secured forms the moi ableauxilir contactvof the circuit breaker. VA corn- -i press'ionspring 24 which is secured at its lower end to "the piston 21 carries at its upper end the auxiliary contact 22. The auxilia with respect to the main contact 20.

The operating solenoid 18 ofthe circuit breaker has a brass tube 30, withinwhich a Cir tubular-armature 3l'reciprocates. An insulatingsleeve 32 separates-the solenoid 18 and the brass tube .30. The lower end of the brass tube passes through an opening in and is secured to the cross head'33 of a bracket supporting the latch mechanism of the circuit breaker.. An annular insulating disk nsulates the solenoidwinding 18 from the cross head 83.

tends the upper terminal of the solenoid coil 18 is seated on to) of the brass tube 30 and 1 c i r cramped thereto by the shoulder on a steel bushing 36 extending through the'opezn mg in the disk and having screw threaded engagement with the inside of the brass;

tube 30; c V a Y I For elevating the piston 21 and the contacts carried thereby afpi'ston rod;37 extending through the bore of the steel bushing 36' is connected with the lower end of the contact tube 20 by means of an 'arbor 38. This arbor 38, as will more fully hereinafterappear, servesas an air intake for the contact tube 20; Clamped between the upper end of the arbor 38 and the end of the piston 21 is an" annular contact'disk" 39 connected with the uppert'erminal of the solenoid coil by a flexible cable 40.

ThemWable auxiliary contact 22 is connected with the piston 21 by a flexible cable a "a inainspring 4:2 is'connected at its '1 upper end withthe arbor 38 and at its lower v contact 22 is therefore movable J V An annular disk. provided with a slot throughwhlch ex end with the steel bushing 36;. This-main spring normally tends to separate the mam contacts. 7 v, V r s The crcsshead 33 of the bracket supporting the latch mechanismhas two downextendinglegs and is carrying A latch 46 pivoted between two tubular armatur'e gl carries at its lower end a plate 52. This plate'521s slotted etween the lower extremities thereof a base 7 retarded by dashpot having an adjustable I cylin d e piston c6 connected with the plate 52. l The latch 46 and dashpot and the supportlug bracliet 13 therefor which extend below end or" sectionfl of the tubular 1e enclosed by the lowensection 2 ubular support. The upper end of lower section-2 fitting within the ferrule 10 is provided with an L-sha'ped'islot 57 1 whiclrallows the lower section to be" locked 111 position by the lower end of the solenoid coil 18 which extends through a slot in the ferrule 15. r

The bottom of through" which the rod 37 extends. .The upper into enga nt with the lower endvof the link 5 or operating the latch46.

ine

.usti-ated circuit breaker mayflbe connected in circuit by inserting theptere between contact clips; This a 7 connection of the'clrcuit breaker in c rcuit minals and 4- requires but a direct thrust movement; whereby the circuit breaker Inay'be easily and quickly connected to and disconnected supported by the plate 4:5 and the section 2" is enclosed by an insulating c1sk58 having anopenlng endoi a push rod 59 carried the, insulatingdisk 58 may be manually moved from the "contact clips. The-guidelfinger 19 Q provided on the lower terminal 1 not only serves to guide and position the circuit breaker in the contact cllps but revents the circuit breaker from being jarred-therefrom uuon the openin of the contacts-of V l g r. the circuit breaker due to the passage of excess current or when the latchis manually released. V a.

To close the contacts of the circuit breaker; the support thereof is held stavtionary while the rod 37 is pushed up until :tl're detent 490i the latch 46 engages the shoulder 50 thereby'holding the rod'in eleiso rated position. .As the rod rises the piston 21 andthe-parts carried thereby are moved upward against the action of the main spring 422 which is therebyput under tension. During the upward movement of the moving parts of the circuit breaker, the moving: auxiliary contact 22 engages the statiou y auxiliary contact 8 whereupon the auxiliary compression spring 24 becomes act-ire. As the upward movement continues this spring 24: is compressed, and the movable main contact 20 moves through the insulating bushing 3 and into the stationar tubular main contact 7 with which it contacts. Figure 2 shows the circuit breaker in closed condition with the main spring 42 under tension and with the auxiliary spring 24 under compression.

The circuit through the circuit breaker may be traced from the terminal 4, through the solenoid coil 18, cable conductor 40, contact plate 39. piston 21, tubular contacts 20 and T and the terminal 3.

When excess currenttraverses the solenoid coil 18, the tubular armature 31 is drawn upwardly within the brass tube 30 carrying with it the plate 52. The dashpot retards the movement of the armature and plate. so that it the excess current is but a surge of short duration the tongue 53 does not engage the link However it excess current flows for a predetermined length of. time. the armature 4A travels far enough spring 24 pushing down thereon. Due to the action of the auxiliary spring 24, the auxiliary contact 22 is maintained in engagement with the auxiliary contact 8 until after the disengagement ot the main contacts 20 and 7, so that themain contacts first disengage and then the auxiliary contacts.

This piston 21 compresses the air in the tubular support when the contacts are separated to provide a blast of air which is blown against and between the auxiliary contacts to prevent the formation of an are or to quench an are which may tend to pert. By mounting the stationary auxiliary disk contact 8 against the bottom of the stationary main tubular contact 7 and by providing the ring barrier 11 in spaced relation to the auxiliary disk contact 8, the blast of air is directed against and between the auxiliary contacts. Destructive prolongation of the arc is thus prevented. and the contacts are preserved.

v dashpot.

By the construction employed, it will be.

This unit. as shownin Fig. 8, may be easily and quickly removed when it is desired to inspect the contacts. Furthermore by mounting these contacts and this terminal asa unit.- such units may be assembled and arried in stock, and when making repairs. it only necessary to remove the damaged unit and replace it with a perfect one.

It will. also be seen that the lower terminal supports the solenoid, the. armature. the movable contacts and the latch and Therefore this terminal and the various parts of the circuit breaker supported thereby may be removed as a unittrom the tubular support.

The circuit breaker is provided with means for manually tripping it, so that when it is desired to inspect the circuit breaker, it may be tripped before removing it from the circuit. By tripping the circuit breaker before it is removed from the circuit the circuit terminals of the circuit breaker and the contact clips engaged by the circuit terminals are protected.

The stationary auxiliary contact is removably carried by the upper terminal. so that when an auxiliary contact becomes damaged it may be easily and quickly removed and replaced by a perfect one.

Obviously other structures may be devised which will embody the invention herein set forth. The drawings and description thereof are therefore to be considered merely in an illustrative and not in a limiting sense.

I hat is claimed is:

1. A circuit breaker comprising a pair of relatively movable contacts, a spring tending to separate the contacts, a latch for holding the contacts in closed relation, an electromagnet responsive upon the occurrence of abnormal conditions to release the latch to allow the spring to open the contacts, and time controlled means for delaying the release of the latch.

2. A circuit breaker for use with contact clips, comprising a tubular support, a pair of circuit terminals carried thereby for co operation with the clips to hold the support in place and complete the circuit, apair of contacts within the support for completing the'circuit between the terminals, one contact being carried by one terminal and the other contact by the other terminal, a spring tending to separate the contacts, a latch carried by one terminal and holding the con tacts in closed relation, an electromagnet within the support carried by one terminal and being responsive upon the passage of excess current to release the latch to allow the spring to open the contacts, and time con trolled meanscarriecl by the electro-magnet the re antl cooperating therewith to delay lease of the latch.

j circuit breaker for. use with contact I 5 clips, compr s nga tubular support a pa r cir terminals carried thereby for con 4 l ertc1 clips to hold i place and complete the circuit a'rnain contactforme l integral with one'terrninal', a removabl a1 V A. ary contactcarried thereby; movable main and munherycontacts Within 7 the snpport latch for holding the mair'r ccntactsin closed relation, a spring tending toseparate the main contacts, an electromagnet ithin the support and responsive causing the-separation t-hereoi uponthe pas to the passage of excess current to release hthe latch to ellow the spring to open the main contacts, and means controlled by the eleetro-rnagnet for causing the auxiliary con- 20 tacts to separate after theopening of the main contacts." 1

4; ll circuitbreaker comprising a pair of relatively movable main contacts having sliding engagement an felectro-Inagnet' for sage of excess current an lli'arycontacts also controlled the electro i'nagnet to open subsequently to the separation of themain contacts-said auxlhary contacts having abuttin engagement, and means controlled by the electromagnet'for. producing a blast of r i saw.

the support 6. A ci cuit, breaker comprisinga pair of" circuit terminals, a pair of main contacts in h the terminals, an electro-rna-gnet circuit responsive uponlthe passage of excess ;cu rrentto open the main contactgancl a pair of 1 acts, and a barrier ooopereting' with the auxiliary contacts also controlled loy the electro-rnagnet to open after the SGjDZLI'fllQlOIl' 7 of the main contacts; one of. the auxiliary contactsbein removabl carried b one of the circuitterminals, means for manually tripping the circuit breaker to open the main contacts.

scribed my name.

Witness whereof, I have hereunto sub- 

